This paper introduces an empirical strategy to estimate dynamic treatment effects in randomized trials that provide treatment in multiple stages and in which various noncompliance problems arise such as attrition and selective transitions between treatment and control groups. Our approach is applied to the highly influential four year randomized…

Serious interest in reducing class size often begins with a key question: What available evidence would support the higher implementation costs? This article discusses positive results of a longitudinal statewide study in Tennessee (Project STAR) and uses findings to specify four guidelines for practitioners and policy makers. Evaluation plans…

A short overview of an experimental evaluation of lower teacher-pupil ratios is presented in this report. The research under review is the Student Teacher Achievement Ratio (STAR) project. This longitudinal project was conducted in Tennessee and was designed to prove to state legislators the efficacy of smaller class sizes. For STAR, evaluation…

This study investigated the possible causes of the contradiction between the results of two projects. Indiana's Prime Time project compared the achievement of students in large (averaging 26 students) and small (averaging 19 students) classrooms in grades 1 through 3. Results indicated that 3 years in smaller classes had little effect on student…

A 3-YEAR EXPERIMENTAL PRIMARY-GRADE READING PROGRAM CONDUCTED WITH A 50 PERCENT REDUCTION OF READING CLASS SIZE WAS EVALUATED IN THE RIVERSIDE, CALIFORNIA, UNIFIED SCHOOL DISTRICT FOR THE YEARS 1962-1965. TEST SCORES WERE ANALYZED FOR 656 CHILDREN IN THE EXPERIMENTAL GROUP WHO HAD 2 OR MORE YEARS OF EXPERIENCE IN THE EXPERIMENTAL PROGRAM AND FOR…